REQ: SHT31 - Address change on SKU:SEN0385, multiple sensor on single board

Hello,

I haven't found anything related to it....

I have this SHT31 sensor and found this guide https://wiki.dfrobot.com/SHT31_Temperat ... KU_SEN0385

My problem is that i have no clue how to change 0x44 address to 0x45.
They say in the code:
* @n When the ADR is connected to VDD, the chip I2C address is 0x45.
* @n When the ADR is connected to GND, the chip I2C address is 0x44.

1. But when i opened it and removed plastic sealing i see only this...so i assume it cant be changed easily
see pics

2. I have also other type of SHT31 sensors , where i should bridge 2 connections in order to change address, but not sure which ones. Haven't found any guide to that...

3. How to solve if i would like to use 3-4x SHT31 sensor in my project? on Cable length around 4 meters each.
As i want to replace DHT22 which are becoming faulty after few weeks, but they were easy to add on PINs without limitations

On since i2C i can add 2x SHT31 (if ill be able to change address) , but how to manage others? (im using also LCD on i2C)

I read about software i2C but not sure how reliable is it.
Also Multiplexer - here might be possible that ill could connect it on 2m long cable and this way i could have 4x 2m sensor on it. But again not sure about stability...

Any tips would be appreciated , thanks!